AP Statistics study help, unit by unit
Isotoon helps with AP Statistics by animating the ideas that formulas hide, like a sampling distribution forming from many samples or a confidence interval catching the true value. Find your unit below and ask what is confusing you.
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AP Statistics, unit by unit
Unit 1: Exploring One-Variable Data
Describing a distribution's shape, center and spread with graphs and summary statistics, and the normal distribution.
Unit 2: Exploring Two-Variable Data
Two-way tables, scatterplots, correlation, least-squares regression lines and residuals.
Unit 3: Collecting Data
Sampling methods, bias, and the design of observational studies and experiments, including random assignment.
Unit 4: Probability, Random Variables, and Probability Distributions
Probability rules, conditional probability and independence, random variables, and the binomial and geometric distributions.
Unit 5: Sampling Distributions
How a statistic varies from sample to sample, sampling distributions for proportions and means, and the central limit theorem.
Read: Central limit theoremUnit 6: Inference for Categorical Data: Proportions
Confidence intervals and significance tests for one proportion and for a difference of two proportions, and Type I and Type II errors.
Read: Confidence intervalsUnit 7: Inference for Quantitative Data: Means
The t-distribution, and confidence intervals and significance tests for one mean, a difference of means and paired data.
Read: P-valuesUnit 8: Inference for Categorical Data: Chi-Square
Chi-square tests for goodness of fit, homogeneity and independence.
Unit 9: Inference for Quantitative Data: Slopes
Confidence intervals and significance tests for the slope of a regression line.
How to use it across the year
AP Statistics is a course about reasoning under uncertainty. The calculations are often done by calculator; what costs points is not knowing what a number means. Get the idea clear before the procedure.
- Ask about the idea behind the procedure. The core three are the central limit theorem, confidence intervals and what a p-value means.
- Then practice with released free-response questions from the College Board, and read the scoring guidelines closely: they show how much the wording of a conclusion matters.
- Rewatch each video 1, 3, 7, 14 and 30 days after you made it, as your notebook lists them.
For a review plan, see how to study for exams without forgetting.
What the exam asks you to do
The exam asks you to choose a method, check its conditions, carry it out and write a conclusion in the context of the problem. Interpretation questions are common: what an interval, a p-value or a slope says about the situation, and what it does not. Check the College Board course page for the current format.
Where students get stuck
- Reading a p-value as the probability that the null hypothesis is true.
- Saying a 95% confidence interval has a 95% chance of containing the true value after it has been calculated.
- Mixing up the distribution of the data, the distribution of a sample and the sampling distribution of a statistic.
- Forgetting conditions such as randomness and independence before running inference.
- Claiming causation from an observational study, when only a randomized experiment supports that.
What Isotoon does and does not do
Isotoon explains ideas with short narrated videos, and on Pro, graphs you can change, such as a sampling distribution that builds as you add samples. It is not a practice-test bank and it does not grade your conclusions. The statistics page has more questions, and exam prep covers review.
Questions
- Is Isotoon affiliated with the College Board?
- No. AP is a trademark registered by the College Board, which is not affiliated with and does not endorse Isotoon.
- Does Isotoon run statistical tests for me?
- No. It explains what a test does and how to read its result. Use your calculator or software for the computation.
- Which AP Statistics topics trip students up most?
- Interpreting p-values and confidence intervals, telling sampling distributions apart from data distributions, and checking conditions before inference.
AP is a trademark registered by the College Board, which is not affiliated with, and does not endorse, Isotoon. Check the College Board’s course page for the current units and exam format.